Novus can be bought in many places, some locally....
Novus comes in 3 main types - #1, #2, and #3. #2 is the one you want to use.
You can by a small-bottle pack of all 3 at The Container Store if you have one local.
Also, the larger bottles sell for about $8 and are usually found at automotive performance parts shops. Motorheads use it to polish the inside of engine cylinders. Whenever I need on fast, I run to a local performance shop and pick one up off the shelf.
**NOTE** Performance shops do not mean AutoZone's, NAPA parts, etc... Performance shops are places you would buy custom cold-air intakes, mufflers, etc to supe up your car. Look in the yellow pages and call them to see if they sell Novus....